Seismic Behaviour Of Steel Fibre-Steel Reinforced Concrete Joints Under The Cyclic Reversed Loading

Common reinforced concrete has a remarkable defect that is weak in tension and is very brickie. So concrete is subject to cracking, especially in complex stress aera. These defects result in low shear load and poor aseismic behavior. Steel Fibre Reinforced concrete(SFRC) and Steel Reinforced Concrete(SRC) have high shear load and good aseismic behavior by comparison. For the sake of getting higher shear load and better aseismic behavior, integrating the advantage of SFRC and the advantage of SRC, we bring forward Steel Fibre-Steel Reinforced Concrete(SF-SRC). Steel Fibre-Steel Reinforced Concrete (SF-SRC) is that the steel Fibre is mixed into Steel Reinforced Concrete.The paper carrys out a test including 6 joints under the cylic reversed load. The author analyses the specimens' mechanics capability and aseismic behavior though studying the test results. Details as follow:1. The paper carrys out a test including 6 specimens of joints under the cylic reversed load. The specimens are divided into 3 groups. The strain and displacement and load of every stage of test are gathered.2. The details of specimens, the process of test and the main phenomena of the specimens during the test are introduced.3.The 3 major crack-modes that occured in test are described. At the same time, the reason cracks occurred is analysed. In addition, the paper analyses that the steel fibre has an catabatic effect on crack.4. Basing on analysing of the hysteretic load-displacement loops of all specimens, the aseismic behavior of specimens is explored in flowing aspects: transform capacity, energy dissipating capacity ductility and stiffness deterioration edt. And the effects of steel fibre and hoop on aseismic behavior of specimens are discussed.5. The mechanism of force resistance of joints is analyzed by the investigation of the data got from the test. The model of force resistance is put forward. At the same time, the equation calculatting ultimate shear-resistant capacity of the joint and the equation calculatting crack-resistant capacity of the joint are presented.6. The bond deterioration of bar and steel shapes is analyzed, and the factors of bond deterioration are studied. The effects of bond deterioration on aseismic behavior of specimens and the mechanism of force resistance of the joint are discussed.